1 files changed, 20 insertions, 0 deletions
diff --git a/js/src/tests/test262/prs/3994/built-ins/Uint8Array/prototype/toBase64/alphabet.js b/js/src/tests/test262/prs/3994/built-ins/Uint8Array/prototype/toBase64/alphabet.js
new file mode 100644
index 0000000000..7edf0a379e
--- /dev/null
+++ b/js/src/tests/test262/prs/3994/built-ins/Uint8Array/prototype/toBase64/alphabet.js
@@ -0,0 +1,20 @@
+// |reftest| shell-option(--enable-uint8array-base64) skip-if(!Uint8Array.fromBase64||!xulRuntime.shell) -- uint8array-base64 is not enabled unconditionally, requires shell-options
+// Copyright (C) 2024 Kevin Gibbons. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-uint8array.prototype.tobase64
+description: Conversion of Uint8Arrays to base64 strings exercising the alphabet option
+features: [uint8array-base64, TypedArray]
+---*/
+
+assert.sameValue((new Uint8Array([199, 239, 242])).toBase64(), "x+/y");
+
+assert.sameValue((new Uint8Array([199, 239, 242])).toBase64({ alphabet: 'base64' }), "x+/y");
+
+assert.sameValue((new Uint8Array([199, 239, 242])).toBase64({ alphabet: 'base64url' }), "x-_y");
+
+assert.throws(TypeError, function() {
+  (new Uint8Array([199, 239, 242])).toBase64({ alphabet: 'other' });
+});
+
+reportCompare(0, 0);